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	<title>020-基本数据类型.html</title>
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	console.log(typeof a);
	console.log(typeof b);

	var oBox=document.getElementById('box');
	console.log(oBox);
	console.log(typeof obox);

	var b=3.1415926;
	console.log(b);
	console.log(typeof b);

	var c ="789";
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	var d =false;
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	var f=123;
	f.name="tom";
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